Pump Up the Volume

Pump Up the Volume is a movie starring Christian Slater, Samantha Mathis, and Anthony Lucero. Mark runs a pirate radio station and causes an uproar when he speaks his mind and enthralls fellow teens.
Mark Hunter, a lonely high school student, uses his shortwave radio to moonlight as the popular pirate DJ "Hard Harry." When his show gets blamed for a teen committing suicide, the students clash with high school faculty and the authorities.